Absorbent articles such as sanitary napkins, pantiliners, and incontinence pads are devices that are typically worn in the crotch region of an undergarment. These devices are designed to absorb and retain liquid and other discharges from the human body and to prevent body and clothing soiling. Sanitary napkins are a type of absorbent article worn by women in a pair of panties that are normally positioned between the wearer's legs, adjacent to the perineal area of the body. Sanitary napkins both with and without side flaps (or wings) are disclosed in the literature and are available in the marketplace. Some particularly preferred sanitary napkins that do not require flaps are described in U.S. Pat. No. 4,950,264 and 5,009,653 issued to Osborn on Aug. 21, 1990 and Apr. 23, 1991, respectively.
Generally when sanitary napkins are provided with flaps, the flaps extend laterally from a central absorbent means and are intended to be folded around the edges of the wearer's panties in the crotch region. Thus, the flaps are disposed between the edges of the wearer's panties in the crotch region and the wearer's thighs. Commonly, the flaps are provided with an attachment means for either affixing the flaps to the underside of the wearer's panties or to the opposing flap. The flaps are particularly effective for preventing exudates from soiling the edges of the wearer's panties.
Sanitary napkins having flaps of various types are disclosed in U.S. Pat. No. 4,687,478, entitled "Shaped Sanitary Napkin With Flaps", which issued to Van Tilburg on Aug. 18, 1987; U.S. Pat. No. 4,608,047, entitled "Sanitary Napkin Attachment Means", which issued to Mattingly on Aug. 26, 1986; U.S. Pat. No. 4,589,876, entitled "Sanitary Napkin", which issued to Van Tilburg on May 20, 1986 and its Reexamination Pat. No. B14,589,876, Certificate of Reexamination issued Apr. 27, 1993; U.S. Pat. No. 4,285,343, entitled "Sanitary Napkin", which issued to McNair on Aug. 25, 1981; U.S. Pat. No. 3,397,697, entitled "Disposable Sanitary Shield For Undergarments", which issued to Rickard on Aug. 20, 1968; and, U.S. Pat. No. 2,787,271, entitled "Sanitary Napkin", which issued to Clark on Apr. 2, 1957.
While sanitary napkins having flaps are commonly viewed as providing better protection against soiling as compared to sanitary napkins without flaps, some women find applying sanitary napkins having flaps to be inconvenient for various reasons. For instance, some women find it to be difficult to attach the flaps to the underside of the crotch of their panties. This can be due to factors such as the tendency for the adhesive fasteners on the flaps to stick to themselves or to other parts of the sanitary napkin. As a result, some women still prefer a sanitary napkin without flaps, and some women who generally prefer a sanitary napkin with flaps, occasionally (such as during periods of light flow) prefer a sanitary napkin without flaps. Therefore, there is a need for a sanitary napkin which provides an alternative to sanitary napkins having conventional side flaps while still providing the protection of side flaps.
In addition, both sanitary napkins with and without flaps are subject to the problem that the wearer's undergarments move with the wearer's movements during wear. These stresses may cause the sanitary napkin to shift from its desired position in the wearer's undergarment. Most sanitary napkins, however, provide no mechanism for adjusting to these movements. This puts stresses on the sanitary napkin and the flaps. The failure to provide the sanitary napkin with a mechanism to adjust to the difference between the movement of the wearer's undergarments and the wearer's body may also cause the sanitary napkin to be not as comfortable as it could be than if it stretched and conformed with the wearer's movements and to the wearer's undergarments.
Several variations of sanitary napkins having conventional flaps that attempt to solve some, but not all of these problems are disclosed in the patent literature. For example, U.S. Pat. No. 4,911,701 issued to Mavinkurve discloses a sanitary napkin having elastic strands for providing a greater convex shape to the body-facing portion of the central absorbent and for enabling adhesive-free placement of the flaps of a winged napkin embodiment into a pair of panties. The sanitary napkin described in this patent, however, still appears to require the user to manipulate the flaps (by first flipping the flaps upward and then placing the flaps in her panties and flipping the flaps back down) since the flaps appear to be pre-disposed to be in a downward folded condition. The Mavinkurve patent also requires that individual elastic strands be attached in a contracted condition to the central absorbent portion of the napkin and/or to its wings or flaps. The napkins described in the Mavinkurve patent can, therefore, be difficult and expensive to manufacture. The Mavinkurve patent also does not disclose any mechanism to account for differences in movement and extensibility of the central absorbent of the napkin and the wearer's panties.
U.S. Pat. No. 4,940,462 issued to Salerno discloses a sanitary napkin with longitudinally expandable flaps. The flaps are designed to fold over the exterior of the wearer's panty and then to expand to conform with the contour of the panties. The Salerno patent, however (in Column 5), appears to require conventional adhesive fasteners to retain the flaps in place on the underside of the wearer's panties. Further, the sanitary napkin shown in the Salerno patent suffers from several drawbacks due to the fact that the longitudinally expandable flaps extend directly outward from the longitudinal sides of the absorbent element. The expandable flaps in Salerno are attached directly to an inextensible body. This limits the extensibility of the portions of the Salerno flaps that are located adjacent to the absorbent element. In order for the Salerno flaps to extend an amount sufficient to wrap around the panty elastics, the flaps have to have a relatively wide transverse dimension. This is shown in FIGS. 3 and 4 of the Salerno reference. The extra flap material can extend too far outward beyond the panty elastics to create a sloppy border that hangs out of the wearer's panties.
Another drawback to the flap construction shown in both the Mavinkurve and Salerno references is that the attachment of the expandable flaps directly to the longitudinal sides of the absorbent element leads to the problem that any compression of the absorbent element will cause the flaps to retract transversely inward. Any bunching of the absorbent element in the sanitary napkins shown in these references, such as that caused by compression by the wearer's legs, causes the flaps to lose their ability to cover a given area of the wearer's panties. The Salerno patent, like the Mavinkurve patent, also does not disclose any mechanism to account for differences in movement and extensibility of the central portion of the napkin and the wearer's panties.
Thus, a need exists for an absorbent article, such as a sanitary napkin, that is provided with an alternative to conventional flaps. In particular, a need exists for a sanitary napkin having an alternative to conventional flaps which provides the protection from soiling of conventional flaps and which can conveniently and efficiently solve the problems caused when attempting to attach conventional flaps to the underside of the wearer's panties and of the failure of the sanitary napkins having conventional flaps to stretch to conform to the wearer's body and the wearer's panties. A need also exists for a sanitary napkin that has a mechanism to adjust to the difference between the movement of the wearer's panties and the wearer's body.
It is, therefore, an object of the present invention to provide an absorbent article, such as a sanitary napkin, that is able to provide coverage to the wearer's panties to reduce side soiling (i.e., staining of the edges of the panty crotch) without the use of conventional flaps.
It is another object of the present invention to provide an absorbent article, such as a sanitary napkin that automatically wraps around the sides of the wearer's panties by the simple action of the wearer pulling up her panties.
It is still another object of the present invention to provide an absorbent article, such as a sanitary napkin, that is able to wrap around the sides of the wearer's panties and stay without providing flaps having panty fasteners thereon, and without attaching separate elastic strands to the sanitary napkin.
It is another object of the present invention to provide an absorbent article, such as a sanitary napkin that has a mechanism for attachment of the sanitary napkin to the wearer's panties that stretches to conform to the wearer's body and the wearer's panties, and responds to the wearer's movements to allow better conformation between the sanitary napkin and the wearer's body and between the sanitary napkin and the wearer's panties.
It is yet another object of this invention to provide an absorbent article, particularly a relatively thin absorbent article, such as a sanitary napkin, that is capable of extending, or more preferably, stretching when the article is worn for improved comfort and fit.
These and other objects of the present invention will be more readily apparent when considered in reference to the following description and when taken in conjunction with the accompanying drawings.